Attention-Deficit/Hyperactivity Disorder (ADHD) is associated with significantly impairing levels of over activity, impulsivity, and inattention, which can deleteriously affect social and academic domains of functioning. Although the extant evidence is abundant regarding the short-term impairments associated with ADHD, the evidence is mixed regarding the predictive risk for drug abuse and juvenile delinquency/adult criminality associated with ADHD. The proposed research is aimed toward understanding the risks and impairments associated with ADHD alone and when co-morbid for CD and non- ADHD comparisons. The specific aims of the proposed research are 1) to gauge the hypothesized differential risk for children with ADHD alone and co-morbid with CD in key domains (e.g., alcohol and other drug use, delinquency), 2) to identify subsets of children (e.g., ADHD subtypes, groups based upon demographic factors and parental factors) that may be at higher risk drug abuse and juvenile delinquency/adult criminality. Current information regarding drug abuse and delinquent and criminal offenses will be gathered from a sample of 500 ADHD children who attended a summer camp for treatment of disruptive behavior disorders when they were between the ages of 6-12 years of a comparison sample of 200 non-ADHD adolescents matched for age, gender, and SES. The ADHD sample will be divided into three developmental stages: early adolescence, mid-to-late adolescence and young adulthood. Because of the large sample size and the availability of diagnostic information gathered while the sample was of elementary school ages, this proposed research will be of especially important in 1) clarifying the conflicting evidence regarding risk for alcohol and other drug abuse and juvenile delinquency/adult criminality associated with ADHD and CD independently and co-morbidity, and 2) identifying other demographic and parental factors that may increase children's risk for drug abuse and juvenile delinquency/adult criminality above and beyond the risk associated with ADHD and CD independently and co-morbidity.